Flavour compounds using ultrasound

21 Feb 2015. NUS food scientists discovered a methodology using high intensity ultrasound processing to generate Maillard reaction flavour at low temperatures.

The generation of desirable flavour compounds through the Maillard reaction is traditionally conducted at high temperatures. A team of researchers led by Prof ZHOU Weibiao and Adjunct Prof Peter K.C. ONG from the Food Science and Technology Programme in NUS have optimized the production of flavour compounds using ultrasound processing at temperatures below 60 °C. They achieved this through experiments with varying conditions followed by mathematical modelling for optimisation. The results of the research conducted by Final Year Honours student Ms Olivia ONG and PhD student Ms SEOW Yi Xin were published in Ultrasonics Sonochemistry recently.

The impact of different initial pH, sonication durations, and ultrasound intensities on the production of Maillard reaction flavour compounds and the extent of Maillard reactions were first determined by headspace solid phase microextraction and gas chromatography-mass spectrometry. The Response Surface Methodology (RSM) was then used to develop production quantity prediction models for two of the Maillard reaction flavour compounds, 2-methylthiophene and tetramethyl pyrazine (see Figure).

This research also revealed that Maillard flavour generation can be included into the growing list of potential applications of high-intensity ultrasound at low temperatures. Additionally, the use of RSM to develop flavour generation prediction models incorporating effects of pH, duration of processing, and ultrasound intensities for Maillard reaction products was also shown to be possible and accurate.

Figure shows a three-dimensional figure of interactive effects of initial pH and time on tetramethyl pyrazine production.. [Image credit: Ong OXH]

Reference

Ong OXH, Seow YX, Ong PKC, Zhou W. “High-intensity ultrasound production of Maillard reaction flavor compounds in a cysteine–xylose model system.” Ultrasonics Sonochemistry (2015) DOI:10.1016/j.ultsonch.2015.01.001.